Chemistry 1.Q2.M6.Week 6 PDF

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General Chemistry 1SELF LEARNING MODULE FOR SENIOR HIGHSCHOOL LEARNERSGrade 11First SemesterQuarter 2, Week 6Note: This Self – Learning Module is only for students of this class. It is not intended for general circulation.Q2/WEEK 6LEARNING COMPETENCY: Describe the structure of proteins, nucleic acid...

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Q2/WEEK 6 General Chemistry 1

SELF LEARNING MODULE FOR SENIOR HIGH SCHOOL LEARNERS

Grade 11 First Semester Quarter 2, Week 6

Note: This Self – Learning Module is only for students of this class. It is not intended for general circulation.

LEARNING COMPETENCY: Describe the structure of proteins, nucleic acids, lipids, and carbohydrates, and relate them to their function (STEM_GC11OC-IIg-j-95)

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BIOMOLECULES

As we study the molecules and ions in living organisms such as humans, we learn that substances with a huge range of sizes and complexities are involved. These include small molecules and ions such as ions, trace metals, ketones, alcohols, and carboxylic acids. Steroids, hormones, vitamins, fats and oils are somewhat larger. We have previously learned that compounds can be categorized as organic or inorganic. This module will focus on a specific set of organic compounds called biomolecules.

At the end of the module, you should be able to: 1) Describe the structures of biomolecules, namely, carbohydrates, lipids, nucleic acids, and proteins; 2) Relate the structures of biomolecules to their functions; 3) Appreciate the importance of biomolecules in daily life.

Direction: Read and answer each statement carefully then write the letter of the best answer. Use your notebook to write your answers. 1. What elements make up a carbohydrate? A. hydrogen, calcium, oxygen C. carbon, potassium, oxygen B. hydrogen, carbon, oxygen D. carbon, magnesium, hydrogen 2. _________ is known as ―animal starch‖. A. Cellulose B. Glucose C. Glycogen D. Lactose Page 1 of 11

3.____________ is the monosaccharide found in starch. A. Fructose B. Glucose C. Lactose D. Maltose 4.__________ is a carbohydrate that cannot be digested by humans. A. Cellulose B. Fructose C. Glucose D. Maltose 5.Long chains of sugars are called _________. A. Polynucleotides B. Polypeptides C. Polysaccharides D. Polyunsaturated

Task 1: To check your prior knowledge about the topic, and to solicit the questions that you want to know about it, fill in the Know and Want to know components of the Know-Want to know- Learned (KWL) chart properly and correctly. For the Know component, you may write word/s or sentence. For the want to know component, state your responses in interrogative or question form. You may list as many responses as you want for each component. Write your responses on a separate sheet of paper. KWL Chart Topic Know Want to Know Learned • Biomolecules

1) Based from what you have written on the Know component of the chart, what do you know about biomolecules? 2) If you were to think of a question that you want to ask about the biomolecules, what question would that be?

. • BIOMOLECULES - Are organic compounds in a living system, and they are generally made up of C,H,O, and/or N, which serve as important parts of cellular structures and metabolic reactions, Their sizes can range from smaller and simple molecules called subunits to bigger and complex structures called macromolecules. A. CARBOHYDRATES. Carbohydrates are compounds made up of carbon, hydrogen, and oxygen. They are also known as saccharides. They have the general formula Cx (H2O)y. Carbohydrates function as the energy source of the body. A simple general classification of carbohydrates is according to the number of sugar units (saccharides) present in the molecule: monosaccharides, disaccharides, and polysaccharides. Page 2 of 11

Monosaccharides are the building blocks or monomers of carbohydrates. The simplest monosaccharide contains three carbon atoms (such as glyceraldehydes and dihydroxyacetone).

Polysaccharides are long chains of monosaccharide that produces polymers. Examples of polysaccharides are starch, cellulose, and glycogen. Starch is composed of glucose monomers linked by alpha-glycosidic bonds and has a general formula of (C6H12O5)x It is the cheapest main energy source of humans, as it is present in a wide array of sources such as rice, corn, potatoes and wheat. It has two major components: a) Amylose is a straight chain that contains 100 to 1000 glucose units and b) Amylopectin is the part responsible for the branching out of chain polymers and contains 500 to 5000 glucose units. Cellulose is the structural component of cell walls that forms the fibers present in plants and wood. Similar to starch, it also comprises glucose units as monomers. However, its glucose units are connected in alternating Page 3 of 11

patterns known as beta linkages. This pattern of connection is responsible for the stiffness of cellulose. B. PROTEINS Proteins are natural polymers. They are very large molecules that are critical for the functions of the human body. They are made from the linkage of monomers called amino acids. Amino acids have the following structure:

Amino acids have two functional groups: a. Carboxylic group (—COOH) and b. Amine group (—NH2) There are 20 kinds of amino acids depending on the —R group. The simplest amino acid is glycine where R is a hydrogen atom. The body cannot make all the amino acids required by the body and is dependent on protein taken through food.

Two amino acids can link together through a condensation reaction with the removal of a water molecule. The linkage is called a peptide bond. Take the case of two amino acids reacting to form a dipeptide.

When many amino acids are linked together through peptide bonds, the resulting molecule is called a polypeptide. A very large number of amino acids linked together results in a protein. Some proteins are made up of only one polypeptide while most proteins involve assemblies of two or more polypeptides. The term polypeptide is usually used for shorter, unstructured chains while proteins fold into fixed structures.

It is therefore possible to think of a protein as a strong of beads strung together where each bead is an amino acid.

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Different Levels of Protein Structure The sequence and the structure of proteins are important in determining their functions. There are four levels of protein structures: the primary structure, secondary structure, tertiary structure, and quaternary structure. The primary structure refers to the linear sequence of amino acids joined by peptide bonds such as the sequence of amino acids below.

The single bonds in the polypeptide chain allow rotation. Therefore, the polypeptide chain can twist and fold in a variety of ways. These folded structures are referred to as secondary protein structures. The two essential secondary structures are the alpha helix and the beta pleated sheets. The structures are stabilized by hydrogen bonds between amino acids. In the alpha-helix structure, the chain twists like a corkscrew while the chain takes the form of a folded sheet in the beta pleated structure. Several secondary structures come together forming tertiary structures. When several tertiary structures come together, a quaternary protein structure is formed. For example, the protein hemoglobin is a quaternary structure formed by four tertiary structures.

Protein Functions Proteins are important molecules in cell. Each protein in the body has a specific function. Some of the types of proteins and their functions are: a. Antibodies - proteins involved in defending the body against antigens. They are the molecules of the immune system. Page 5 of 11

b. Contractile proteins – responsible for body movement such as muscle contraction c. Enzymes – proteins that catalyze (speed up) or facilitate biochemical reactions d. Hormonal proteins – serve as messenger proteins to help coordinate some body functions. An example is insulin (which controls blood sugar concentration). e. Structural proteins – are fibrous and provide support. An example is collagen which provides support to connective tissues. f. Storage proteins – store amino acids like casein in milk. g. Transport proteins – are carrier proteins which move molecules from one place to another in the body. An example is hemoglobin which transports oxygen. Protein Denaturation Denaturation is a process in which a protein loses its secondary, tertiary, or quaternary structures. This may be caused by physical or chemical agents like strong acid, base, inorganic salt, heat, or solvent which disrupt the bonds that hold the protein structures together. Denaturation does not cause the cleavage of the peptide bond (the primary structure). Note that a protein will lose its biological activity if it loses its 3-dimensional shape. Examples of Protein Denaturation DENATURING AGENTS Heat Acids and Bases Heavy metal ions like Ag+, 2+ 2+

Pb , Hg Organic compounds

Mechanical agitation

EXAMPLES Cooking food (boiling egg, frying an egg) Acid denatures milk proteins in the preparation of cheese Mercury and lead poisoning Chemicals used in hairstyling or hair straightening or hair curling Preparation of whipped cream or meringue from egg whites

C. NUCLEIC ACIDS Nucleic acids are natural polymers with very large molar masses. The two main types of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). DNA and RNA are polymers made up of monomers in the form of nucleotides. When these nucleotides combine, they form polynucleotides. DNA carries the genetic information passed on from parents to children. RNA plays an important role in protein synthesis. Each nucleotide is made up of three parts: 1. A nitrogen base a. Purines - adenine (A), and guanine (G) b. Pyrimidines - cytosine (C), thymine (T), uracil (U) 2. A five-carbon sugar Page 6 of 11

a. Deoxyribose b. Ribose 3. Phosphate

Function Structure Sugar used Bases used

DNA Repository of genetic information Double helix deoxyribose C,T,A,G

RNA Involved in protein synthesis Usually single-strands Ribose C,U,A,G

D. LIPIDS Lipids are a class of naturally occurring organic compounds distinguished by their solubility in an organic solvent (and not in water). Lipids are hydrophobic, nonpolar, and made up mostly of hydrocarbon chains. Some of the more important lipids are: triglycerides (fats), saturated and unsaturated fatty acids, waxes, phospholipids, and steroids. Some examples of lipids: 1. Fatty Acids a. Fatty acids consist of a long hydrocarbon chain (typically about 12 – 18 carbons) attached to a carboxyl group. i. Saturated fatty acid – contains only single C-C bonds because the carbon atoms are saturated or filled up with hydrogens. Because their structure is straight, they can pack well and are solid at room temperature (e.g. fat in butter).

ii. Unsaturated fatty acids – contain carbon-carbon double bonds. When there is only one C-C double bond, it is called monounsaturated; if there are several C-C double bonds, they are called polyunsaturated. Remember that when there are double bonds, there will be geometric isomers (cis and trans). Because of the double bonds, they do not pack as tightly as saturated fatty acids. They are usually liquids at room temperature. An example of an unsaturated fatty acid is olive oil.

b. Fats and Oils Fat molecules have two parts: a glycerol backbone and three fatty acid chains. The resulting molecule is called a triglyceride.

2. Waxes – are nonpolar lipids that plants and animals use for protection and have many functions in society. Natural waxes are typically esters of fatty acids and long chains of alcohol. Page 7 of 11

3. Steroids – are another class of lipid molecules, identifiable by their structure of four fused rings.

Task 2: Complete the concept map below.

I have learned that _____________________________________. I have realized that _____________________________________. I will apply _____________________________________________.

(For submission) Test I: Answer what is asked. Write your answer in your notebook. 1) What are the biomolecules of life? 2) What makes carbohydrates different from lipids as a source of energy? 3) What makes starch different from cellulose? 4) Which is healthier: saturated fat or unsaturated fat? 5) What are the functions of RNA and of DNA? 6) Briefly describe the structure of proteins, nucleic acids, lipids, and carbohydrates, and relate them to their function. Page 8 of 11

Test II: Essay Pyrimidine and purine bases always occur in pairs. How about you? Can you work alone, or do you always need other people’s help in doing your tasks?

Glossary Carbohydrate Lipids Nucleic acid Protein

A biopolymer made up of saccharide units Naturally occurring organic compounds distinguished by their solubility in an organic solvent A biopolymer consisting of repeating units of ribose or deoxyribose, phosphate, and selected bases A naturally occurring polymeric chain of 1-amino acids linked together by peptide bonds.

References Espinosa, Allen, et.al., (2016), General Chemistry 1. Makati City: DIWA Learning System Inc. Ginete, Ana Marielle L., (2020), LAS SHS General Chemistry 1 MELC 13 Q2 Week7.pdf. DepEd Region 6 – Western Visayas Holtzclaw Jr., Henry F, et.al., (1991), General Chemistry with Qualitative Analysis Ninth Edition. Lexington Massachusetts Torento: D.C. Health and Company, Licuanan, Patricia, et. al., (2016), Teaching Guide for Senior High School General Chemistry 1 Specialized subject / Academic STEM. Quezon City: Commission on Higher Education. Merritt, Clement. Stereochemistry at Tetrahedral Centers. Accessed August 31, 2020. https://slideplayer.com/slide/9032088/ Rahim, Ahura. Organic Compound. Accessed August 31, 2020. https://www.slideshare.net/Ahura1/organic-compound-71714349 Tapayan, April Sweet, (2020), General Chemistry 1 Quarter 2 Module 1. Department of Education, Division of Cagayan de Oro City. Whitten, Kenneth, et.al., (2007). Chemistry. Eight Edition. United States of America. Thomson Corporation. Page 9 of 11

General Chemistry 1 Module. Alternative Delivery Mode. Accessed/Downloaded August 7, 2020, https://bit.ly/KTO12MODULES The Four Biomolecules Concept Map. Accessed September 2, 2020. https://sciencemusicvideos.com/ap-biology/module-6-menu-biochemistry/thefourbiomolecule-families/ Steroids lipids. Accessed January 1, 2021, https//www.khanacademy.org.

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Answer Key: Try this: 1) 2) 3) 4) 5)

B C B A C

Task 1: Answers may vary. Task 2:

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